iPhone 7 Plus Touch Screen Not Working

Fenómeno del mal funcionamiento

The phone can be turned on normally, but the touch function not working.

Solución de problemas

For the iPhone 7 Plus Touch Screen Not Working issue. Because there is no touch ICs on the motherboard anymore for iPhone 6s and above models. The relevant components are the connector, some small components, and the CPU.

Check the diode values on the touch connector J4502 after replacing a new screen. All the diode values are normal.

Then continue to Measure the voltage values

• PP5V1_TOUCH_VDDH_CONN on FL3911
• PP1V8_TOUCH on C3932

both the voltages are also normal.

Then try to replace another display/touch connector J4502.

After replacing the connector, the no-touch issue resolved.

The repair tip for issues related to accessories, the first step we should check the relevant diode value and voltage values. After checking, if all values are normal, then we can try to replace the connector to have a try.

Sometimes, the issue might be caused by the poor connection or the pseudo soldering of the connector.

iPhone 7 Motherboard Repair Course